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111.
一、深刻领会精神实质,做好规划管理工作 党的十七大召开后,我处紧密结合国土资源管理实际,认真学习和贯彻十七大精神,把深入贯彻落实科学发展观作为规划管理工作当前及今后一个时期的首要任务。通过学习我们感到,一是规划管理工作是国土资源重点工作;二是在资源利用中,规划更要积极参与经济运行宏观调控;三是在规划管理工作中,要进一步提高规划管理水平,提高工作效率、加快办事节奏,提供优质服务。  相似文献   
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拟建的国家重力基本网由100年点组成,其中有15个基准点(绝对重力点)、85个基本点(相对重力点),近2000条测线。本首先对初始设计方案进行了评估,然后根据精度、可靠性、费用等优化目标提出了重力网优化设计需顾及的几条原则。在图形优化设计中,用模拟法计算,删除了部分对精度贡献不大的测线,得到一个略低于精度要求的设计方案。在此基础上分别用解析法和模拟法进行二级优化设计,重新分配观测值的权,得到两处满足要求的设计方案。  相似文献   
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Simulating a lake as a high-conductivity variably saturated porous medium   总被引:1,自引:0,他引:1  
Chui TF  Freyberg DL 《Ground water》2008,46(5):688-694
One approach for simulating ground water–lake interactions is to incorporate the lake into the ground water solution domain as a high-conductivity region. Previous studies have developed this approach using fully saturated models. This study extends this approach to variably saturated models, so that ground water–lake interactions may be more easily simulated with commonly used or public domain variably saturated codes that do not explicitly support coupled lake–water balance modeling. General guidelines are developed for the choices of saturated hydraulic conductivity and moisture retention and relative permeability curves for the lake region. When applied to an example ground water–lake system, model results are very similar to those from a model in which the lake is represented as a specified head boundary continuously updated by a lake mass balance. The high-conductivity region approach is most suitable for relatively simple geometries and lakes with slower and smaller fluctuations when the overall flow pattern and system fluxes, rather than the detailed flow pattern around the intersection of the lake and land surfaces, are of interest.  相似文献   
114.
模拟水氡仪与数字化水氡仪对比观测实验   总被引:1,自引:0,他引:1  
在相同观测条件下,选用平凉地震台北山2号泉水样作为实验目标,用 FD-125型模拟水氡仪与 SD-3B 型数字水氡仪进行对比观测实验;搜集全国用相同方法观测的5个地震台的观测资料进行对比分析,结果表明:FD-125型模拟水氡仪性能明显优于 SD-3B 型数字水氡仪。  相似文献   
115.
宁洱井的水位自2014年10月25日以来持续下降39.2cm,低于正常水位谷值8.335m,2015年的年变幅度为正常年变的57.8%,呈破年变现象。经现场调查,发现周围观测环境干扰小,水位变化量相对可靠;通过分析水位与降雨量的相关性,以及GNSS监测网的位移资料,认为持续低水位异常与降雨量关系不大,属于地震前兆异常,其原因可能与该区域构造的拉张活动有关。总结地震前兆异常的地震活动规律,认为该异常可能对近期滇西南-滇缅交界地区中强地震危险性有指示意义。  相似文献   
116.
Total hydrocarbon and selected polycyclic aromatic hydrocarbon (PAH) levels were examined in sediments collected from known problematic areas in the canals of Venice, Italy, in 1995 and 1998. Hydrocarbon concentrations were greatest in the interior canals, moderate in the partially enclosed locations and lowest in the open-water sites. Total hydrocarbon and PAH concentrations declined from 1995 to 1998. Ancillary data suggest that this decline may have been in response to the elimination of many industrial activities in the lagoon and to initiating an aggressive canal dredging program. The distributions of individual components were generally similar both years regardless of the total PAH concentration or the location of sample collected. PAH alkyl homolog distributions suggest that atmospheric deposition of petrochemical combustion products is the main source of PAHs to Venice's sediments. In some cases however, the presence of low levels of the two-ring naphthalene homologous series indicate additional low-level inputs of fresh oil.  相似文献   
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Tissues of bowhead, beluga, and gray whales were analyzed for Ag, Cd, Cu, Se, Zn, THg and MeHg (belugas only). Delta15N and delta13C in muscle were used to estimate trophic position and feeding habitat, respectively. Trace element concentrations in tissues were significantly different among whale species. Hepatic Ag was higher in belugas than bowheads and gray whales. Gray whales had lower Cd concentrations in liver and kidney than bowhead and belugas and a sigmoid correlation of Cd with length was noted for all whales. Renal and hepatic Se and THg were higher in belugas than in baleen whales. The hepatic molar ratio of Se:THg exceeded 1:1 in all species and was negatively correlated to body length. Hepatic and renal Zn in subsistence-harvested gray whales was lower than concentrations for stranded whales. Se:THg molar ratios and tissue concentrations of Zn may show promise as potential indicators of immune status and animal health.  相似文献   
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